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import QtQuick 2.6
import QtQuick.VirtualKeyboard 2.1

/*!
    \qmltype InputPanel
    \inqmlmodule QtQuick.VirtualKeyboard

    \brief Provides the virtual keyboard UI.
    \ingroup qtvirtualkeyboard-qml

    The keyboard size is automatically calculated from the available
    width; that is, the keyboard maintains the aspect ratio specified by the current
    style. Therefore the application should only set the \l {Item::}{width} and \l {Item::}{y}
    coordinates of the InputPanel, and not the \l {Item::}{height}.

    As with \l {Qt Virtual Keyboard QML Types}{all other QML types} provided by
    the module, the \c QT_IM_MODULE environment variable must be set to
    \c qtvirtualkeyboard before using InputPanel. For more information, see
    \l {Loading the Plugin}.
*/

Item {
    id: inputPanel

    /*!
        \qmlproperty bool InputPanel::active
        \since QtQuick.VirtualKeyboard 2.0

        This property reflects the active status of the input panel.
        The keyboard should be made visible to the user when this property is
        \c true.
    */
    property alias active: keyboard.active

    /*!
        \qmlproperty bool InputPanel::externalLanguageSwitchEnabled
        \since QtQuick.VirtualKeyboard 2.4

        This property enables the external language switch mechanism.
        When this property is \c true, the virtual keyboard will not show
        the built-in language popup, but will emit the \l externalLanguageSwitch
        signal instead. The application can handle this signal and show a
        custom language selection dialog instead.
    */
    property bool externalLanguageSwitchEnabled

    /*!
        \qmlsignal InputPanel::externalLanguageSwitch(var localeList, int currentIndex)
        \since QtQuick.VirtualKeyboard 2.4

        This signal is emitted when \l externalLanguageSwitchEnabled is \c true
        and the \l {user-guide-language}{language switch key} is pressed by the user.

        It serves as a hook to display a custom language dialog instead of
        the built-in language popup in the virtual keyboard.

        The \a localeList parameter contains a list of locale names to choose
        from. To get more information about a particular language, use the
        \l {QtQml::Qt::locale()}{Qt.locale()} function. The \a currentIndex
        is the index of current locale in the \a localeList. This item should
        be highlighted as the current item in the UI.

        To select a new language, use the \l {VirtualKeyboardSettings::locale}
        {VirtualKeyboardSettings.locale} property.

        Below is an example that demonstrates a custom language dialog implementation:

        \snippet qtvirtualkeyboard-custom-language-popup.qml popup

        The dialog would then be declared:

        \snippet qtvirtualkeyboard-custom-language-popup.qml declaring

        In the application's InputPanel, add the following code:

        \snippet qtvirtualkeyboard-custom-language-popup.qml using

        The custom dialog will now be shown when the language switch key is pressed.
    */
    signal externalLanguageSwitch(var localeList, int currentIndex)

    /*! \internal */
    property alias keyboard: keyboard

    /*! \internal */
    readonly property bool __isRootItem: inputPanel.parent != null && inputPanel.parent.parent == null

    SelectionControl {
        objectName: "selectionControl"
        x: -parent.x
        y: -parent.y
        enabled: active && !keyboard.fullScreenMode && !__isRootItem
    }
    Component.onCompleted: setFLWGeometry()
    onWidthChanged: setFLWGeometry()
    onHeightChanged: setFLWGeometry()
    function setFLWGeometry() {
        if(__isRootItem)
            flw.width = Math.min(height*16/15, width)
        else
            flw.width = width
        flw.height = flw.width*3/8
        flw.x = (width-flw.width)/2
        //anchors.horizontalCenter: parent.horizontalCenter #error
        //anchors.bottom: parent.bottom #error
        flw.y =  height-flw.height
    }
    
    implicitHeight: width*3/8
    Rectangle {
        id: flw
        color: "#000"
        property int pan: 24
        property int movThreshold: 4
        property int minimumWidth: 512
        property int minimumHeight: 160+20

        MouseArea {
            //id: top
            acceptedButtons: Qt.LeftButton
            cursorShape: Qt.SizeAllCursor
            property real oldX
            property real oldY
            onPressed: {
                oldX = mouseX;
                oldY = mouseY;
            }
            onPositionChanged: {
                if(pressedButtons === Qt.LeftButton) {
                    var dx = mouseX - oldX
                    var dy = mouseY - oldY
                    if(Math.abs(dx)+Math.abs(dy) > parent.movThreshold) {
                        parent.x = parent.x + dx
                        parent.y = parent.y + dy
                    }

                }

            }
            anchors.top: parent.top
            anchors.bottom: keyboard.top
            x: parent.pan
            width: parent.width-parent.pan*2
            
        }

        MouseArea {
            //id: topLeft
            acceptedButtons: Qt.LeftButton
            property real oldX
            property real oldY
            cursorShape: Qt.SizeFDiagCursor
            onPressed: {
                oldX = mouseX
                oldY = mouseY
            }

            onPositionChanged: {
                if(pressedButtons === Qt.LeftButton) {
                    var dx = mouseX - oldX
                    var dy = mouseY - oldY
                    if(Math.abs(dx)+Math.abs(dy)>parent.movThreshold) {
                        var newWidth = Math.max(parent.width-dx, parent.minimumWidth)
                        var newHeight = Math.max(parent.height-dy, parent.minimumHeight)
                        parent.x = parent.x + (parent.width-newWidth )
                        parent.y = parent.y + (parent.height-newHeight)
                        parent.width = newWidth
                        parent.height = newHeight

                    }


                }

            }
            y: 0
            x: 0
            height: parent.pan
            width: parent.pan

        }
        MouseArea {
            //id: bottomLeft
            acceptedButtons: Qt.LeftButton
            property real oldX
            property real oldY
            cursorShape: Qt.SizeBDiagCursor
            onPressed: {
                oldX = mouseX
                oldY = mouseY
            }

            onPositionChanged: {
                if(pressedButtons === Qt.LeftButton) {
                    var dx = mouseX - oldX
                    var dy = mouseY - oldY
                    if(Math.abs(dx)+Math.abs(dy)>parent.movThreshold) {
                        var newWidth = Math.max(parent.width-dx, parent.minimumWidth)
                        parent.x = parent.x + (parent.width-newWidth )
                        parent.width = newWidth
                        parent.height =  Math.max(parent.height+dy, parent.minimumHeight)

                    }
                }
            }
            height: parent.pan
            width: parent.pan
            y: parent.height-height
            x: 0


        }
        MouseArea {
            //id: topRight
            acceptedButtons: Qt.LeftButton
            property real oldX
            property real oldY
            cursorShape: Qt.SizeBDiagCursor
            onPressed: {
                oldX = mouseX
                oldY = mouseY
            }
            onPositionChanged: {
                if(pressedButtons === Qt.LeftButton) {
                    var dx = mouseX - oldX
                    var dy = mouseY - oldY
                    if(Math.abs(dx)+Math.abs(dy)>parent.movThreshold) {
                        parent.width = Math.max(parent.width+dx, parent.minimumWidth)
                        var newHeight = Math.max(parent.height-dy, parent.minimumHeight)
                        parent.y = parent.y + (parent.height-newHeight )
                        parent.height = newHeight

                    }
                }
            }
            height: parent.pan
            width: parent.pan
            y: 0
            x: parent.width-width

        }
        MouseArea {
            //id: left
            acceptedButtons: Qt.LeftButton
            property real oldX
            property real oldY
            cursorShape: Qt.SizeHorCursor
            onPressed: {
                oldX = mouseX;
                oldY = mouseY;
            }

            onPositionChanged: {
                if(pressedButtons === Qt.LeftButton) {
                    var dx = mouseX - oldX
                    var dy = mouseY - oldY
                    if(Math.abs(dx)+Math.abs(dy)>parent.movThreshold) {
                        var newWidth = Math.max(parent.width - dx, parent.minimumWidth)
                        parent.x = parent.x + (parent.width-newWidth)
                        parent.width = newWidth
                    }

                }

            }
            y: parent.pan
            x: 0
            height: parent.height - parent.pan*2
            width: parent.pan

        }
        MouseArea {
            //id: right
            acceptedButtons: Qt.LeftButton
            property real oldX
            property real oldY
            cursorShape: Qt.SizeHorCursor
            onPressed: {
                oldX = mouseX;
                oldY = mouseY;
            }

            onPositionChanged: {
                if(pressedButtons === Qt.LeftButton) {
                    var dx = mouseX - oldX
                    var dy = mouseY - oldY
                    if(Math.abs(dx)+Math.abs(dy)>parent.movThreshold) {
                        parent.width = Math.max(parent.width + dx, parent.minimumWidth)

                    }

                }

            }
            height: parent.height - parent.pan*2
            width: parent.pan
            y: parent.pan
            x: parent.width-width


        }
        MouseArea {
            id: bottom
            acceptedButtons: Qt.LeftButton
            property real oldX
            property real oldY
            cursorShape: Qt.SizeVerCursor
            onPressed: {
                oldX = mouseX;
                oldY = mouseY;
            }
            onPositionChanged: {
                if(pressedButtons === Qt.LeftButton) {
                    var dx = mouseX - oldX
                    var dy = mouseY - oldY
                    if(Math.abs(dx)+Math.abs(dy)>parent.movThreshold) {
                        parent.height = Math.max(parent.height + dy, parent.minimumHeight)
                    }


                }

            }
            y: parent.height-height
            x: parent.pan
            height: parent.pan
            width: parent.width-2*parent.pan

        }
        MouseArea {
            id: bottomRight
            acceptedButtons: Qt.LeftButton
            property real oldX
            property real oldY
            cursorShape: Qt.SizeFDiagCursor
            onPressed: {
                oldX = mouseX;
                oldY = mouseY;

            }
            onPositionChanged: {
                if(pressedButtons === Qt.LeftButton) {
                    var dx = mouseX - oldX
                    var dy = mouseY - oldY
                    if(Math.abs(dx)+Math.abs(dy)>parent.movThreshold) {
                        var newWidth = Math.max(parent.width+dx, parent.minimumWidth)
                        var newHeight = Math.max(parent.height+dy, parent.minimumHeight)
                        parent.width = newWidth
                        parent.height = newHeight
                    }

                }

            }
            height: parent.pan
            width: parent.pan
            y: parent.height-height
            x: parent.width-width
        }

        Text {
            text: InputContext.preeditText
            x: keyboard.x
            y: 0
            width: keyboard.width
            height: keyboard.height/10
            color: "white"
            font.pixelSize: height*5/8
            leftPadding: 20
        }

        Keyboard {
            id: keyboard
            width: Math.min((parent.height-parent.pan)*128/49, parent.width-parent.pan*2)
            anchors.horizontalCenter: parent.horizontalCenter
            anchors.bottom: parent.bottom
            anchors.bottomMargin: parent.pan
        }
        MouseArea {
            z: -1
            anchors.fill: keyboard
            enabled: active
        }
    }

    Binding {
        target: InputContext.priv
        property: "keyboardRectangle"
        value: mapToItem(null,
                         __isRootItem ? flw.x : x,
                         __isRootItem ? flw.y : y,
                         flw.width,
                         flw.height)
        when: !InputContext.animating
    }
}
